The present invention relates generally to the field of cartridge loaders. More specifically, the present invention relates to loaders which sequentially load each of a plurality of cartridges into a cartridge drive.
Most personal and small business computers were originally designed for the use of flexible or floppy disk memories. Devices for the unattended sequential loading of floppy disks have been developed for a variety of uses. These devices generally include a hopper wherein the disks are stacked for loading into a disk drive. Generally, these devices have been used for making multiple copies of the same program. The use of these devices for storage of large amounts of data on disks has generally proven unsatisfactory due to the large number of disks involved and the difficulty in retrieving data from them.
To ensure the interchangeability of flexible disk and other drives, an industry standard has been established which requires that these drives be constructed so that they fit within a "full height form factor" (of approximately 3 1/4 inches (8.3 cm) in height by 5 3/4 inches (14.6 cm) in width by 8 inches (20.3 cm) in length) or a "half height form factor" (of approximately 1 5/8 inches (4.1 cm) in height by 5 3/4 inches (14.6 cm) in width by 8 inches (20.3 cm) in length).
The 5 1/4 inch (13.3 cm) tape drive has achieved great popularity for backing up the data of a personal or small business computer, due to its high storage capacity and rapid data access capability. However, more recently, R-DAT drives have been developed which store much more data within an even more rapid data access capability. Most users prefer internal drives. The increasing standardization of the computer industry requires that these internal R-DAT drives, like all drives, fit within the full or half height form factor described above.
A standard R-DAT tape may hold up to 1.3 gigabytes of data. However, many applications, including archival storage, journaling, online and background storage, and the unattended back-up of large amounts of data, may require storage of several times that amount of data. When backing up a data source of more than 1.3 gigabytes, it is necessary to change the R-DAT tape in a R-DAT cartridge drive approximately every two hours. Since most such backing up is done outside of normal work hours to avoid tying up the computer holding the data, it is often not convenient to change the R-DAT tape. Thus, there is a need for a cartridge loader capable of holding a plurality of R-DAT cartridges for loading sequentially into a R-DAT cartridge drive.
Many computer systems include a plurality of memory storage drives. Indeed, the half height form factor drives are often stacked one on top of the other. Access to all of these drives must be preserved when any accessory, including a cartridge loader, is added to the computer. In order for a cartridge loader to be used most conveniently, it would be desirable to obviate the need to attach and detach the loader for each use. An attached loader which does not block access would need to be adapted to fit within the small 1 5/8 by 5 3/4 inch (4.1 by 14.6 cm) space of the front of the half height form factor. Thus, there is a need for a loader adapted to fit within that space.
Devices for loading and unloading cartridges have been developed. However, many of these devices are adapted for use only with certain low storage capability cartridges, such as standard audio cassettes. Moreover, many of these devices are quite large and expensive. Many users do not require such large devices, and cannot afford to pay for them. Other loading/unloading devices include an external cartridge drive, resulting in less consumer satisfaction due to preferences their for internal drives and the greater size and expense of the external drives. Many of the devices require an electrical or logical interface with the host computer. The interface requirement restricts the use of the devices to systems for which interfaces have been developed. Thus, there is a need for a small, relatively inexpensive cartridge loader which loads cartridges into an internal tape drive and does not require an electrical interface with the computer to be loaded.
Recently, Predator Systems Corporation announced the development of the Data Hawk I, a 4 mm DAT stacker holding eight DAT cartridges for loading and unloading to a 4 mm DAT cartridge drive. The Data Hawk I has a load/unload cycle time of over 15 seconds and has an anticipated enduser price of approximately $4000. The long cycle time and relatively high price of the device may prove unacceptable to many users. Thus, there remains a need for an inexpensive automated cartridge loader with a short load/unload cycle.